Screed structure



Aug. 9, 1960 A. s. MILLIKIN SCREED STRUCTURE 3 Sheets-Sheet 1 Filed July 3. 1957 INVEN TOR ARNOLD S. MILLIKIN BY CORBETT, MAHONEY 8. MILLER,ATTYS.

J ML

Aug. 9, 1960 A. s. MILLIKIN 2,948,202

SCREED STRUCTURE Filed July 3, 1957 3 $heets-She et 2 9.1: I I I LGTIIIIIILT:

IN V EN TOR. ARNOLD S. MILLI KIN CORBETT, MyY 8. MI LLER,ATTYS.

BY %MI My invention relates to a screed structure.- More specifically, it relates to an adjustable-end shoe and baflie for a screed structure of a pavementfinisher. my invention will be described with reference to a concrete finishing machine, it is not necessarily limited thereto.

shown as being of the type which operates on suitable side forms and which comprises a frame 10 carried by the wheels 11 which cooperate with the forms. The screed structure 12 is supported at the front of the frame 10 and in a machine of this type is usually mounted for trans- Although In the past, it has been customary to provide a fixed from bleeding outwardly along the screed beyond the ends of the "screed and the forms. When the machine is being used for laying a pavement of standard width, there is no problem with the fixed end shoes but when the pavement is of non-standard width or is of gradually changing width, such as at, curves or merging lanes, it would be. desirable to vary the spacing between the shoes accordancewith the variation in width of the pavement as determined by the variation in spacing ofthe side forms. This has been accomplishedinthe past by bodily removing and resetting the shoes in different positions onthe screed. However, it would be desirableito have adjustable shoes which could be readilyadjusted'gradu allyin accordancewith the width variations'without reinoval and resettingof shoesi y It is the main object of my invention'to provide" a screed structure with an adjustable end shoe and-bathe on each end, which is somounted on the screed and has -adjusting mechanism associated therewith of such a nature that the shoe can berea'dily adjusted whenever desired with ease positively and accurately in accordance with pavement width variations and without removal and resetting of any parts. Various "other advantages will bev apparent.

' The preferred embodiment of 'my invention is 'illustrated in the accompanying drawings. However, it is to be understood that it can take other forms without departing from the basic principles'of my invention.

In the drawings: t .1 Figure l i-sa perspective view showing the screed-structure. with 'the adjustable end shoe andbaflie 'of my verse reciprocation, for example, by means of the pivots 12a and 12b or in any other suitable manner. The adjustableend shoe and bafile units 13 are disposed at each end of the screed 12. The finishing machine will advance over the side forms and over the spread layer of concrete andwill level 01f and finish the surface to the level of the forms. An excess of material will be accumulated as the screed 12 ismoved along the forms butit will be-prevented from bleeding past the ends of this screed 12 and the for-msby means of'the units 13, as shown in Figure 1.- a 5 As shownin the drawings, the screed 12 is of rigid construction, being substantially in the form of a box girder which will span thewidth of the pavement and will res't on the side forms. The screed includes the lower surfacing plate 14 and the :front upright plate 15, the plate 14 having an upturned flange 16 with its upper edge'disposed'behind the lower edge of the plate 15, as shown in Figures 4 and 6. The upright flange 16 and the upright plate 15 will engage the'mateiial which acalong the forms. 1 a

- As 'previouslyindicated, at each end of the screed 12 one of the end shoe and bafiie units 13 is'mounted. For mounting such unit, each endof the screed is provided with a guide upon which theshoe is mounted for slidable movement-longitudinally of the screed. This guide is-in the formof an upright guide plate 17 which is secured to "the front'screed plate 15 andiextend's longitudinally thereofi It is fastened to the front plate 15 by means of the". bolts 18' which pass through the plate 17 and through'longitudinally extendingspacer' strips 19 disposed-adjacent the upper and lower edges of the guide cumulates infront of the screed-"as the screed pushed plate 17. f This provides an outwardly opening guide groove or channel 20 a both'the upper and lower edges of the plate 17 since the corresponding edges of the spacer strips 19 are spaced within the edges of the guide plate.

Each. shoe and baffle unit 13 is provided with a vertically; disposed rear wall'21. (Figures 1 and 6) which'will be disposed directly ahead ofitheguide plate 17. 'This wa-l1'21 has bolted'to itsrear side, by means of'the bolts 22, the upper and lower inwardly directed guide flanges These flanges are spaced-rearwardly from the rear surface of the wall 21 by means of the spacer bars 24 and thebolts 22 pass through'thesebars as wel'l' as invention shown on a schematic illustration of pavement "finisher omitted.

Figure 2 is a front elevational view of one end of the screed structure showing the associated adjustable shoe and baffle unit and its adjusting mechanism.

Figure 3 is a transverse vertical sectional view taken along line 3-3 of Figure 2.

Figure 4 is a transverse vertical sectional view taken along line 44 of Figure 2.

Figure 5 is a plan view of the structure shown in Figure 2.

Figure 6 is a transverse vertical sectional view taken along line 6-6 of Figure 5.

Figure 7 is a sectional view taken along line 7-7 of through the uide flange 23 and the wall 21. The uide usages 23f wil1 project into -th'e guide grooves zo'anatne guide plate 17 will extend outwardly into the guide grooves 25 between the wall 21 and the flanges 23. It will be noted that the spacer bars 24 are slightly thicker than the plate 17 to prevent binding of the edges of the plate in the grooves 25. Furthermore, it will be noted that the spacer strips 19 are slightly thicker than the guide flanges 23 to prevent binding of the flanges in the grooves 20 between the guide plate 17 and' the screed front plate 15. Thus, it will be apparent that the unit 13 is mounted on the end of the screed 12 by sliding movement thereon. without the danger of binding. The guide structure is adequate to' take the backward and upward thrusts on 3 v the uni-t 13 as the screedis advanced over and through the concrete material.

The unit 13 comprises the lower shoe 26 (Figures 1, 4 and 6) whichis at the same level as the lower surfacing plate 14 of the screed 12;. It iswe'ldedito the lower edge of the rear wall 21 'and extends rearwardly beyondthe wall to a point closely adjacent the upright fian'ge'16' of the plate 14. The unit 13 further includes the upright end bafiie 27 which has its inner end fastened to the upright rear Wall 21. The baffle 27 extends angularly outwardly, straightforwardly and then laterally, as shown in Figures 1 and 5, and the forward edge of the shoe 26 is of similar contour. The shoe 26 slides over the surface of the material and the upright bafile 27;prevents lateral bleeding of the material beyond theends of the screed.

To move each unit 13 longitudinally of the guide plate 17, an adjusting screw 30 is provided. This adjusting screw is mounted at the top side of the screed 12 so that it will be out of the material which accumulates in front of the .screed adjacent the lower surface thereof. This screw 30 is rotatably mounted at its outer end in a bearing bracket 31 '(Figures 1, 3 and which is attached .to a forwardly extending plate 32 bolted, by the bolts 33, to the top plate 34 of the screed 12. The screw 30 is rotataw bly mounted in a bushing 35in the bracket 31. The opposite end of the screw is keyed to a thrust sleeve 36, as shown in Figure 7. The opposite ends of the sleeve 36 engage the thrust collars 37 which are mounted on the sleeve. The outer collar 37 engages an upstanding bracket 38 which has a bushing 39 therein that rotatably receives a reduced bearing end 40 of the screw'30. The inner collar 37 engages a similar upstanding bracket .41 which has an opening that rotatably receives the screw 30. The brackets 38 and 41 are spaced axially of the screw and screed and are mounted on a plate 42 which is rigidly fastened to the top portion of the screed 12, as indicated best in Figure 5.

As indicated in Figure 6, the screw 30 is threaded through a sleeve 43. This sleeve 43 is anchored in a bracket sleeve 44: which is rigidly secured to the upper end of a. bracket 45 (Figures 1, 2, 5 and 6) that is rigidly at tached to the upstanding wall 21 and the horizontal shoe 26 of the unit 13'. The outer end of the screw 30 is squared, as indicated at 46, to receive a crank or ratchet wrench by means of which the screw may be rotated in face, means for mounting 'said shoe and baffle unitfor;

either direction. It will be apparent that when the screw 30 is rotated, since it is mounted to prevent axial movement but to permit rotative movement, the screw will thread in and out of the sleeve 43 carried by the bracket 45. Consequently, the unit 13 will be moved along the guide plate17 in a direction depending upon the direction of rotation of the screw.

It will be apparent that the shoe at either end of the screed 12 can be adjusted readily by turning the proper screw 30. Thus, as the machine moves along the side forms and they either converge or diverge, due to the curving or angling of the side form at either side, the shoe and bafile unit 13 at the proper end of the screed may be quickly and positively adjusted by turning the screw 30 and will be held in adjusted position until it is desired to again adjust such unit. The units 13 are mounted so that there will be no binding to interfere with adjustment, even though the unit is taking considerable upward andrearward thrusts from the material into and over which it is advanced. The screw mechanism'is located at a high point so that the material will not accumulate thereon and tend to interfere with the proper operation thereof.

Various other advantages willbe apparent.

According to the provisions of the patent statutes, the principles of this invention have beenexplained and have been illustrated and described in What is now considered to representthe best-embochment: However, it-is tobe understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

Having thus described my invention, what I claim is:

l. A screed adapted to extend over side forms to engage and act on the surface of paving material disposed therebetween, said screed being of fixed length and having an upright material-engaging forward face against which surplus material may accumulate as the. screed is moved along the side forms, an end shoe and baffle unit at each end of the screed andhaving: an upright material-engage ingface extending forwardly. from said forward screed:

movementlongitndinally of the screed was to move the upright material-engaging face of the unit along the upright material-engaging face or; the screed, and means connected betwen the screed and each unit for positively and-indepenently moving. such unit on the end of thescreed in accordance with variations inspacing between the side forms to move said shoe and bafile face of said unit adjacent the cooperating side form to prevent any of said surplus material which may accumulate in front-of said uprightscreed face from feeding outwardly over said side form. n

2. The combination of claim 1 in whicheach shoe and bafile unit comptises a flat shoe and an upright forwardly and outwardly directed baffle above the shoe providing said upright material-engaging face thereon, said mounting means of each unit comprising means for slidably' mohnt ing the unit on the screed, saidmoving means of each comprisinga screw operatively connected to the unit and the screed. V V

3. Thecornbination of claim 2 in whichthescrew or each unit is disposed at theupper side of the screed and means is provided for rotatably mounting the screw on the screed but for preventing axial movement thereof relative to the screed, a member fixed to saidshoe and bafiie unit through which said screw is threaded, said unit including an upright rear wall located'at the rear edge of said shoe and at the rear and inner end of said bafii 'e, said material-engaging faceof the screed being provided by an upright front well, said mounting means forthe unit come prising a guide structure betwen said front wall and said rear wall for permitting-the slid-able movement of theunit relative to the screed.

, 1,662,257 Valerio Mar. 13,192 2,299,700 Millikin a a1 Oct. 20, 1942 2,591,502 Bohemian et a1. Apr. 1,1952 

